crc8tab.c

Error checking CRC and CRC TABLE GENERATORS in C Language

#include <stdio.h>

#define POLINOMIO 0x8D

int main()
{
	FILE *fp;
	unsigned int c;
	int k, crc;

	if((fp=fopen("crc8.txt", "wr"))==NULL)
	{
		printf("ERRO AO ABRIR O ARQUIVO");
		return 1;
	}

	fprintf(fp, "unsigned char crc8[256] = {");
	for(c=0;c<256;c++)
	{
		crc=(unsigned char)c;
		for(k=0;k<8;k++)
		{
			if(crc&128)
			{
				crc=(crc<<1);
				crc^=POLINOMIO;
			}
			else crc=(crc<<1);
		}
		if(!(c%4)) fprintf(fp, "\n");
		if(c!=15) fprintf(fp, "%d, ", crc);
		else fprintf(fp, "%d };", crc);
	}
	fclose(fp);

	return 0;
}